Downtown shooting

Police superintendent Garry McCarthy, left, walks from a building at 231 S. LaSalle St., where an executive of a Loop company shot and killed himself after critically wounding the CEO of the firm in a dispute over a demotion.

Police superintendent Garry McCarthy, left, walks from a building at 231 S. LaSalle St., where an executive of a Loop company shot and killed himself after critically wounding the CEO of the firm in a dispute over a demotion. (Nancy Stone, Chicago Tribune)

Police superintendent Garry McCarthy, left, walks from a building at 231 S. LaSalle St., where an executive of a Loop company shot and killed himself after critically wounding the CEO of the firm in a dispute over a demotion.